Energy-absorbing interruptor



April 30, 1968 G. L. HAZELET ETAL 3,380,385

ENEHGYAMSORB ING INTERRUTOH 2 Sheets-Sheet 1 Filed Dec.

G. HAzl-:LET ETAL 3,380,385

ENERGY-ABSORBING INTERRUITOR April 3o, 196s 2 Shams-Sheet il;

Filed Dec. 8, 1965 Zas United States Patent O 3,380,385 ENERGY-ABSORBING INTERRUPTOR Gerald Lynn Hazelet, Urbana, and Larry Ervin Wilson, Champaign, Ill., assignors to The Magnavox Company,

Fort Wayne, Ind., a corporation of Delaware Filed Dec. 8, 1965, Ser. No. 512,452 18 Claims. (Cl. 1112-76) ABSTRACT F THE DISCLOSURE An energy-absorbing interruptor for explosive devices has a bendable or yieldable plate in the explosive train. In the unarmed position, the plate absorbs energy from a detonator to prevent explosion of the main charge.

This invention relates generally to fuzes and more particularly to an interruptor in an explosive train and which includes an energy-absorbing barrier.

A typical explosive train may consist of a detonator to provide the pilot explosion as a result of a minimal energy input, an explosive link (lead) to increase the magnitude of the explosion, a booster element to further stepup the explosive force and hot gas output, and finally, the warhead proper. In such a train, the detonator has maximum sensitivity, `and the degree of sensitivity of other elements decreases to a minimum sensitivity in the warhead proper. Safety of handling is normally provided by maintaining tihe detonator and lead out of alignment while at the same time interposing a barrier or interruptor material of suliicient thickness and appropriate design to prevent propagation of the explosion. To insure explosive propagation when desired, the lead is moved into alignment with the detonator and booster to provide a continuous train of explosive to initiate the warhead.

Although the removal of the lead from alignment with the detonator and booster is a rst step to prevent accidental explosion of the `booster Vand warhead, it has been common practice to interpose a solid piece of material between the detonator and booster after removal of the lead. This has been accomplished primarily by one of two methods. In a shutter or slider method, a member is provided containing the lead and containing a solid piece of material and is movable between a position wherein the lead is aligned with the detonator and booster, and an unarmed position wherein the solid material is interposed between the detonator `and the booster. If a detonat-or is exploded while the device is in the unarmed position, the output is directly into the solid metal rather than into the lead or the booster. This method is often used when space is critical.

The other method frequently used is the rotor method wherein a solid piece of material containing the lead is mounted with its axis perpendicular to the detonator axis. In the unarmed state, the solid portion of the rotor is interposed between the detonator and the booster. If the detonator is exploded, its output is directed into the curved portion of the cylindrical rotor.

The aforementioned methods have disadvantages including the necessity of a thick section of solid material in the shutter method, as well as heavy supporting sections to prevent transmission of .shock from the detonator to the booster. The rotor method consumes a large amount of space in the axial direction and requires heavy 3,380,385 Patented Apr. 30, 1968 "ice supporting bearing surfaces to prevent its separation from the supporting structure and subsequent transmission of shock to the booster. Little if any detonator blast energy is absorbed by either method and most of the blast is detlected by the heavy structures. If the blast energy is great enough, it is possible for the shock thereof to be transmitted toward the booster.

It is therefore a general object of the present invention to provide an improved safety feature in explosive trains.

A further object is to provide an interruptor which .actually absorbs the explosive force and hot gas output of the detonator and minimizes shock transmittal to supporting structure and, therefore, to the booster.

A further object is to provide an interruptor maximizing the safety of handling characteristics of the device.

Described briefly, in a typical embodiment of the present invention, `a movable member of the shutter-type, the slider-type, or the rotor-type is mounted between the detonator and the booster in an explosive train. The movable member has a lead charge therein which is movable by the member to a position out of line with the detonator and booster. The member also includes a yieldable portion disposed in front of the detonator when the device is in the unarmed condition and which will absorb the blast of the detonator if it is accidentally tired. The yieldable member is arranged so as to absorb energy by using the energy to permanently bend and deform it. It lalso can absorb the energy by heat absorption, erosion and melting. Meanwhile, another portion remains intact, spaced from the yieldable portion and shielding the booster.

The full nature of the invention will be understood from the accompanying drawings and the following description and claims:

FIGURE 1 is an elevational view of an explosive device, with a portion broken away to show the incorporation of an embodiment of the present invention therein.

FIGURE 2 is an enlarged section of a portion of the device of FIGURE l.

FIGURE 3 is a section like that of FIGURE 2 but illustrating the effect of exploding the detonator when the device is in the unarmed condition.

FIGURE 4 is a view of a slider-type interruptor, this being on approximately the same scale as FIGURES 2 and 3.

FIGURE 5 is a section like those of FIGURES 2 and 3 but illustrating a rotor-type of interruptor according to the present invention and as it might be incorporated in the device of FIGURE 1.

FIGURE 6 is another view of the rotor of FIGURE 5 in the armed position as it is in FIGURE 5.

FIGURE 7 is a view like FIGURE 5 but showing the rotor in the unarmed position `and deformed by an aceidental explosion of the detonator.

FIGURE 8 is a diagram of another variation of the present invention wherein the basic technique is ernployed for sequential gas porting.

Referring now to the drawings in detail, FIGURE 1 shows an explosive device 11 having a nose 12 and a firing pin 13 therein, the pin 13 being operable, when actuated, to strike and fire the detonator 14. The interruptor 16 of the present invention is shown in the armed position and has a lead charge 17 therein. An explosive booster 18 is provided next to the main explosive charge 19. So it is seen that an explosive train is provided wherein the sensitive detonator 14 is aligned with a less sensitive lead charge which is aligned with a still less sensitive booster charge 18 which is next to the comparatively insensitive main charge 19. When the tiring pin strikes the detonator and explodes it, a chain of explosions is established with the lead charge and then the booster and then the main charge, in conventional manner.

The interrupter 16 is shiftable in the housing from an unarmed condition to the armed condition of FIG- URE. 1, and for this purpose the interruptor 16 is rotatable on the axis 21 by any suitable arming mechanism 22 in response to some condition such as spin speed, pressure, time, or any other desired condition. Devices for this purpose are well known in the art and need not be described. Suice it to say that normally the interruptor 16 is arranged so that the lead charge 17 is disposed as shown in FIGURE 2 which is much out of alignment with the axis 23 of the explosive train, the detonator discharge, and the booster. In other embodiments of the invention the interruptor is also shiftable', linearly in the slider type and rotationally or arcuately in the shutter and rotor types.

According to the embodiment of the present invention which is illustrated in FIGURE 2, the interruptor 16 includes a circular disk 24 and a circular disk 26, both of which are aixed to the p-ivot post 27 mounted for rotation in the housing 28 on the axis 21. These disks are typically made of metal and the portion 24A of disk 24 is disposed in front of the point at which the detonator discharges when it is tired. The metal plate 26 is parallel to plate 24 and spaced apart therefrom as shown, with a substantial air gap 29 between these plates. The lead 17 extending between the plates and remote from detonator and booster in FIGURE 2, is protected by the sleeve 31.

FIGURE 3 shows what occurs when the firing pin 13 is driven into and explodes the detonator 14 whereupon the hot gas discharging therefrom impinge on the upper plate 24 and distort it as shown. The mechanical work required to distort the plate 24 is derived from the explosion of the detonator so that a large portion of the energy initially stored in the detonator is absorbed in the yielding of the plate to its distorted condition. At the same time, because of the sturdy mounting of the post or shaft 27 to the bulk head 32, there is no danger of the plate 26 being driven into the booster. In fact, while the plate 24 is being bent toward plate 26 in the air gap 29, plate 26 covers the booster and shields it from the blast. Moreover, the blast is detiected as shown at 33, in a direction transverse to the axis of the explosive train, and away from the lead charge 17.

Because some time is involved in bending the plate 24 during the detonator blast, additional energy is absorbed in heating, erosion, and melting of the plate by the high temperature and velocity of the gases expelled by the detonator. All of this time, the plate 26 is shielding the booster from the eects of the detonation. Plate 26 is not at all affected by the blast. So while plate 24 is undergoing substantial plastic deformation as it is permanently distorted, plate 26 need not even undergo elastic deformation.

So it is seen that because of the detiection and mounting of the plate 24 so it can yield un-der pressure from the blast, the blast energy is actually absorbed in and by the interruptor itself, and transmission of shock therefrom to the housing is minimized and transmission of shock to the booster and lead are minimized. Thus, the present invention oters a degree of protection to the lead and booster which has heretofore been unattainable.

Referring now to FIGURE 4, a slider-type of interruptor is shown, being viewed in a direction parallel to the axis of the explosive train with which it would be employed. In the particular device the lead charge 17 is again secured to a pair f plates disposed in parallel vertically spaced relationship like those of FIGURES l, 2 and 3, with upper plate 36 thereof having a portion broken away to show the lower plate 37. These plates may be atiixed in the vertically spaced relationship to each other by three rivets 38, for example, with a large area to the right of one of these rivets being provided for disposition below or above the detonator. The location of the detonator relative to the plates when the slider is in the unarmed position is shown by the dotted outline 39. To arm the device, the slider would be moved in the direction of the arrow 4l to position the lead charge 17 in alignment with the detonator and the other elements of the explosive train.

Referring now to FIGURE 5, the explosive device is provided with a tiring pin 13 therein, detonator 14, booster 18, and main charge 19. In this instance, however, instead of having the shutter disk type of interruptor of FIGURES l, 2 and 3, or the slider-type of FIGURE 4, the rotor-type of interruptor is used. This rotor 42 is mounted for rotation on an axis 43 transverse to the explosive train axis 23. It is arranged with suitable bearing and actuating means 44 at opposite ends thereof to rotate it degrees on the axis 43 from the safe position shown in FIGURE 7 to the armed position shown in FIGURES 5 and 6.

This rotor includes an outer cylindrical plate 46 and an inner cylindrical plate 47 provided with an air space 48 in the center and the annular air gap 49 between the two cylindrical plates or cylinders. These plates are affixed to each other in coaxial spaced relationship by end plates 51, one of which is shown in FIGURE 6.

Aligned apertures S2 are provided in the rotor cylinder 46 and are aligned with similar apertures in the cylinder 47. The exp-losive lead charge 17 is received in a sleeve 53 extending across the cylinders 46 and 47 and having its cylindrical axis colinear with the line through the centers of the apertures 52. Accordingly, when the rotor is in the armed condition shown in FIGURES 5 and 6, it is possible `for the blast 14 from the detonator to initiate the lead charge 17 whereupon the blast therefrom initiates the booster 18.

When the `rotor is in the unarmed position as shown in FIGURE 7, and the detonator is fired accidentally as by activation of the firing pin 13 or otherwise, for example, the blast therefrom is directed onto the surface 54 of the outer cylinder and this, being `made of yieldable material bends inwardly toward the axis 43 as shown in FIC- URE 7. As it does so, it absorbs the energy of the detonator blast. The end plates 51 also bend inwardly at both ends in the region designated by the reference numerals 56 to absorb additional energy. At the same time, the blast direction is altered so that it is generally outwardly toward the outer wall 28 of the 'device at the portions of the wall intercepted by a line parallel to the axis of the lead enclosure sleeve 53 when disposed as shown in FIG- URE 7, and passing through the discharge area 58 immediately under the detonator. So it is clear that the lead charge itself is protected not only from shock but also from the heat, and so is the booster protected and shielded therefrom.

In FIGURE 8, a gas generator S9 is provided with an outlet passage 61 which is flared outwardly at 62 and covered by an interruptor plate 63. This plate is affixed in a housing 64 at 66 and is immovable except by yielding outwardly from the mounting point 67. In the illustrated embodiment, three outlet ports 68, 69, and 71 are arranged in the housing 64 in adjacent sectors thereof. To control the yielding of the plate 63 and obtain an arcuate motion thereof from the position shown by the soli-d outline to the position 72 shown by the dotted outline, the portion at 67 is thinner than elsewhere on the plate. Accordingly, when the gas generator establishes a sufliciently high pressure discharge at the plate 63, the plate is bent at 67 and moves outwardly in an arcuate fashion in the direction of the arrow 73. It thus uncovers the ports 68, 69 and 71 in sequence, assuming of course that the pressure and volume available from the gas generator is suficient to deflect it the full distance. Thus we have a means for using the yieldable interruptor of the present invention to distribute gas through ports in sequence. This can be used when a rapid sequencing of valves or distribution to gas utilizing items is desired.

Examples of materials which could be used for yieldable plates are mild steel, brass, and any other nou-brittle material capable of absorbing the amount of energy stored in the detonator. Naturally the dimensions of the air gap and the plate itself, the moment arms from the rigid mounting points, the erosion characteristics, and the available discharge volume in the housing 28, for example, can be varied as desired to obtain the optimum combination depending on the energy potential of the particular detonator being employed.

The gas generator S9 in FIGURE 8 can be of whatever sensitivity an-d capacity are desired for the particular application, and could also be a detonator, if desired.

While the invention has been disclosed and described in some detail in the drawings and foregoing description, they are to be considered as illustrative and not restrictive in character, as other modifications may readily suggest themselves to persons skilled in this art and within the broad scope of the invention, reference being had to the appended claims.

The invention claimed is:

1. In a Huid handling device, the combination comprisa uid pressure generator having a point of discharge;

a yieldable member disposed in front of said discharge point to obstruct fluid discharge therefrom, said generator being capable of discharging fluid under sufiicient pressure and at such a rate as to cause at least a portion of said member to yield and become distorted during discharge of fluid at said point;

and a housing for said yieldable member, said housing having a plurality of output ports spaced apart and normally isolated from said discharge point by said yieldable member;

said yieldable member being mounted for a portion thereof to move during the yielding thereof past a first and second of said output ports in sequence to provide communication between said discharge point and said first port and to then provide communication between said discharge point and both said first and second output ports for discharge of fluid from said first port and then from said first and second ports.

2. The combination of claim l wherein:

the mounting of said yieldable member fixes one portion thereof and said movable portion swings generally arcuately about said one fixed portion, said ports being arranged generally in adjacent sectors of said housing.

3. In a uid handling device, the combination comprising:

a fluid pressure generator having a housing, a point of discharge, and an explosive detonator mounted in said housing;

and a yieldable member disposed in front of said discharge point to obstruct fluid discharge therefrom, said generator being capable of discharging uid under suflicient pressure and at such a rate as to cause at least `a portion of said member to yield and become distorted during discharge of fluid at said point;

said yieldable member being shiftable in said housing from a position in front of said discharge point when desired prior to explosion of said detonator to a position that avoids impediment thereby to fluid clischarge by said detonator upon explosion thereof.

4. The combination of claim 3 and further comprising a shiftable mounting member in said housing, said mounting member having an explosive charge mounted thereon and having said yieldable member thereon, said charge being located thereon so as to be shifted thereby to a position in `front of said discharge point when said yieldable member is shifted away from in front of said discharge point.

5. The combination of claim 4 wherein:

said shiftable mounting member has a shield member thereon spaced from said yieldable member, with an air gap between said yieldable member and said shield member and permitting deflection of said yieldable member toward said shield member during absorption of energy of fluid discharge by said yieldable member upon explosion of said detonator.

6. The combination of claim 5 and further comprising:

a third explosive separated yfrom said detonator by said yieldable member, said air gap, and said shield member when said yieldable member is in front of said discharge point.

7. The combination of claim 5 wherein:

said yieldable member and said shield member are parallel at metal plates.

8, The combination of claim 5 wherein:

a support post is affixed to and supports said yieldable member and said shield member, said support post being disposed between said explosive charge and said portion which yields and distorts, to thereby protect said explosive charge from transmission of shock from said portion thereto.

9. The combination of claim 5 wherein:

said detonator has a discharge axis;

said yieldable member and said shield member are mounted in said housing for rotation on an axis other than said detonator axis to enable said yieldable member and said charge to be shifted rotationally between an unarmed condition and an armed condition.

l0. The combination of claim 5 wherein:

said yieldable member and said shield member are radially spaced coaxial cylinders mounted in said housing for rotation on their axis between an uuarmed oriented and an armed orientation.

11. The combination of claim 5 wherein:

said mounting member is a slider.

12. The combination of claim 5 wherein:

said mounting member is a shutter.

13. The combination of claim 5 wherein:

said mounting member is a rotor.

14. In a uid handling device, the combination comprismg:

a uid pressure generator means;

absorber means associated with said generator means and movable from an unarmed position where it obstructs Huid discharge from said generator means to an armed position; said absorber means having the material thereof plastically deformable by the uid discharged from said generator means and thereby being capable of absorbing energy from said uid when in said unarmed position.

15. In an explosive train, the combination comprising:

a first explosive;

a second explosive of less sensitivity than said first explosive and spaced apart therefrom;

a movable member having a first portion with a third explosive therein of sensitivity intermediate those of said iirst and second explosives, said movable member having a second portion interposed between said first and second explosives and preventing communication therebetween, said movable member being movable to an armed position providing communication between said third explosive and said first and second explosives to enable precipitation of a chain of explosions by said first explosive and propagated thereby through said third and second explosives;

said second portion being yieldable by explosion of said rst explosive when said second portion is interposed between said first and second explosives to absorb the energy of explosion of said first explosive,

said second portion being mounted at a point between said rst explosive and said third explosive and thereby yieldable in a direction dellecting the blast of explosion of said rst explosive in a direction away from said third explosive. 16. The combination of claim 15 wherein: said movable member has a third portion disposed between said second explosive and said first explosive and said rst portion and preventing communication therebetween and shielding Said Second explosive from the effects of detonation of said irst explosive. 17. The combination of claim 16 wherein said third portion is mounted to prevent deflection thereof upon detonation of said first explosive when said second portion is deflected.

18. The combination of claim 16 wherein said second Cit and third portions are normally spaced apart, and said second portion is deected in the air space between said second and third portions, during detonation of said first explosive.

References Cited BENJAMIN A. BORCHELT, Primary Examiner. SAMUEL W. ENGLE, Examiner.

G. H. GLANZMAN, Assistant Examiner. 

